Bearing



Dec. 10, 1935.

H. A. s. HOWAPTH 2,023,764

- BEARINC Original Filed April 12, 1927 jg 3nventor Wad. own MA.

attorney I ?atented Dec. 10, 1935 i 2,023,764

UNITED STATES PATENT OFFICE BEARING Harry A. S. Howarth, Philadelphia,Pa., assignor to Kingsbu'ry Machine Works, Inc., Frankford,Philadelphia, Pa., a corporation of Delaware Original application April12, 1921, Serial No.

183,135. Divided and this application Decemher 21, 1928, Serial No.327,664

28 Claims. (Cl. 308-421) This invention relates to bearings, and morether arrangement-of oil grooves in circumferenparticularly to combinedthrust and steady beartial development; and

ings, although certain features thereof are appli- Fig. 4 is a schematicsection showing another cable to journal bearings generally. Thisappliembodiment of this invention comprising a com- 5 cation is adivision of application Serial No. billed ust and steady ar 5 183,135,filed April 12, 1927, Patent No. 1,760,904, ri g to Fig. 1 of th d awi ts aft 5 granted June 3, 1930 of the present applicant. is shown disposedhorizontally in a steady bear- It is an object of this invention toprovide a ing II wh is a d y a shell 1 having fi steady bearing or otherform of journal bearthereto an oil pot 6. While only a steady or jouringwith a novel arrangement of oil grooves a bea is ow in this figure. itis to be 10 whereby the drawing of air into the oil film may understoodthat it is to be associated immediately be prevented, or whereby the oilfilm produced with a thrust bearin if s d s The s ell or may be sodisposed as to maintain the desired s ee e 1 0f the St ad? or journalbearing is shown. balance of the oil film axially of the bearing, or asprovided intermediate its length with opposed whereby vibration of theshaft may be prevented, spherical surfaces 8 Which Contact With p 15 orcontrolled, or whereby a combination of these to s su a es 9 o t esuppor It for sa d results may be obtained if desired. shell, the suppbeing s w a taking e f m Another object of this invention is to provideof a P s w supported i ny u bl Way. a novel steady bearing supportwhereby the steady thus rendering the steady 1 Journal ei e 0 bearingmay be made self alining, if desired. self-aiming; The shell 1 may be ein halves Another object of this invention is to provide for convenienceof assembly, i so eslreda self-.alining steady bearing with oil gro Thepresent invention involves novel principles which maintain the desiredbalance of the oil film in the arrangement f a a e of 1 grooves withrespect to the axis about which alinement is p y for pp y t e Surface ofthe bearefiectei ing with lubricant, and is applicable not only to 25Another object of this invention is to provide steatiy beailligs sshel'eshown, but o t loul'nsl a novel combined thrust and steady, bearingbearings m ywherein the lubrication of the steady bearing is In theembodiment s ed in F g. 1, shaft 5 effected from the oil provided forlubricating the cooperates W the s at onary bearin ember t t H, whichmay be a lournalbrass or a babbitt 30 Another object of this inventionis to provide a bushing be of any suitable nstruction. The combinedthrust and steady bearing which is pos- Oil is delivered to u er nt algroove or sessed of any desired combination of the features Chamber med1 the sleeve 'I or m the rear above referred to. oi the bush ng II, andflows therefrom through a,

Other objects will appear as the description of plurality ofcircumierentially arran e p r ure 35 the invention proceeds. l3,disposed in a medial circumferential line, into The invention is capableof receiving a variety plurality of axially nd ng oil grooves H in rm fthe bushing H. The oil flow-- of mechanical expressions, several ofwhich are t P 3 face drawin but it is to mg into the grooves l4 dividesand flows 1n opposhown on the accompany} g g site directions toward theextremities of the bear- 40 be expressly understood that the drawing isor v purposes of illustration only and is not to be conmg Surfaces forP01121011 0f the length o strued as a definition of the limits of theinveng g aplgoxlmatzly gl -3 their 1 eng an en ows on war y rougpastlomfieffrence being had to the appended claims sages s5 g onpassages or c hers s formed for t a g i' d in wherein the a in thesleeve 8 or in the bushing H, which l 45 Refenmg o e raw lead toward theopposite extremities of the bearreference f i are employed designate ingsurfaces. From the passages or chambers l6 corre p h Po t Severalfiguresi the oil flows inwardly to the bearing surfaces Fi 1 is anaxlftl Sectlon of Journal through passages W and thence to the oppositebearing embodying the Present mventlon and extremities of the bearingsurfaces through 50 illustrating a novel arrangement of oil grooves;grooves is formed in the stationary bearing Fi 2 is diaglammatic Viewillustrating face. Said grooves l8 terminate in circumferenotherarrangement of oil grooves in circumferenti l 1 l r ov la in thestationary bearing tial development; surface, disposed adjacent theopposite extremities Fig. 3 is a diagrammatic view illustrating afurthereof, from which the oil flows through suitable 5 openings I! topassages 20 in the bushing II or shell 1 or both, which are connected tothe oil reservoir 2|. A passage 22 in the shell I is illustrated forconveying the oil from the remote groove 20 to the reservoir 2|, and thenear groove 20 is shown as discharging directly into said reservoirthrough suitable openings.

. The surplus oil which cannot pass through the openings l9 flows alongthe bearing surface into the channel 20 formed between the end ofbushing l I and shell I, and returns to the oil reservoir throughpassage 22.

It will be noted that the air seal grooves l9 are maintained filled withoil at or above atmospheric pressure duringv the operation of thebearing. Hence, if the oil film pressure adjacent these grooves shouldfall to or below atmospheric pressure, the grooves will supply oilthereto, preventing the entrance of air, and preserving the integrity ofthe film. The channel 20 is merely a drain to prevent the oil fromworking along the shaft outside the bearing. Obviously, additional oildrain grooves may be used if deemed desirable.

Thus, in this embodiment, the oil is delivered to the bearing surfacesat a medial circumferential line and flows in opposite directions to theextremities of the bearing surfaces, where the oil is collected incircumferential grooves l9 adjacent the extremities of the bearingsurfaces. Moreover, the grooves l8 at each extremity of the bearingsurfaces are of the same length as and in alinement with thecorresponding grooves at the opposite extremity, and said grooves iiiare also in alinement with the ,medial line between successive grooves Hwhich latter grooves extend axially of the bearing surfaces to an equalextent on either side of the circumferential medial line and inalinement with the medial line between the grooves l8. Therefore, theoil grooves are symmetrically arranged with respect to the medialcircumferential line of the bearing.

This disposition of the oil grooves effects a balance of the pressuresin the oil films with respect to the medial circumferential line of thebearing surfaces.- Thus when any given element of the bearing surface ofthe shaft is opposite a groove M, where the oil pressure falls nearly toatmospheric. the shaft is supported at either side of the groove H bytwo oil films of equal sire extending between the grooves It on theopposite sides of the axial line It. When said element is opposite apair of grooves l8, so that the oil pressure adjacent the extremities-ofthis line drops nearly to atmospheric, the shaft is supported midway ofthe length of the bearing surfaces by an oil film extending between thepair of grooves I 4 on either side of the line passing through thegrooves I8, and this film extends equally on opposite sides of themedial circumferential line. This condition is true for every element ofthe bearing surface of the shaft and therefore the shaft is supportedthroughout its bearing surface by films which are balanced axially ofthe shaft with respect to the medial circumferential line, so that thereis less tendency for unbalanced films to set the shaft into vibration.This is particularly important where the bearing is self-alining so thatthe stationary bearing member has facility of movement and may be setinto vibration by unbalanced oil film pressures.

The proper bearing action is further aided by the presence of thecircumferential grooves is adjacent the opposite extremities of thebearing passing through the groove surfaces. These grooves are normallymaintained full of oil and therefore act as air seals, preventing theadmission of air into the films between the bearing surfaces, andtherefore preventing the film being destroyed with the consequent lack 5of support of the shaft by an oil film pressure where such occurs. It isto be noted that all of the oil grooves of this embodiment extendaxially of the shaft, and therefore they have no pumping action on theoil, but the quantity of oil flowing 10 therethrough depends entirelyupon the quantity and pressure of the source. With this arrangementthere is no danger of the oil grooves pumping the oil out of the bearingsurfaces more rapidly than it is delivered thereto. However, the airsealing oil grooves at the extremities of the bearing surfaces may beemployed with other arrangements of oil grooves, as hereinafterexplained, including helical arrangements whereby the grooves effect apumping action, and whether an or not the oil grooves are so arranged asto give balanced films. In general, films balancedaxially of the shaftare obtained when the oil grooves are symmetrically arranged withrespect to a circumferential medial line so that every ele- 25 ment ofthe shaft surface is acted upon by balanced moments of pressure, andwith this limitation the oil grooves may be inclined to the axis orhelical, so as to have a pumping action, or they may cross each other orbe reverse helices, etc. On the other hand, a lack of symmetry resultsin a lack of balance in the oil film,- and vibrations in the shaft maybe set up. This may be taken advantage of to set up a predeterminedvibration in the shaft which is different from the 35 normal tendency ofthe shaft at its own period or the period of vibration of the partsconnected thereto, so as to effect a dampingaction on the vibration ofthe shaft. The oil may be delivered to the groove or chamber l2 in anysuitable way 40 as by a viscosity pump. In the form shown in Fig. 1, theshaft 5 carries a channel-shaped oilcollecting ring 23 which at itsupper end overhangs the end of thesleeve I, so that oil taken up by saidring from the reservoir 2| delivers the 5 same to a groove or channel 24which communicates with a passage 25 in the sleeve 1, leading to thegroove or chamber i2. The channelshaped oil-collecting. '.ring 23 ispreferably made in halves which may be hinged together and 50 clampedaround the shaft 5 by any suitable lock or retaining means suclf fas isdiagrammatically illustrated at 26. i

In the embodiment shown in Fig. 1 the oil is delivered to the bearingsurfaces in a medial cir- 55 cumferential line, but this is notessential, as the oil may be delivered to the bearing surfaces at thesealing grooves at one extremity of the bearing surfaces, and be causedto fiow lengthwise of the bearing surfaces, discharging through the 60opposite oil sealing grooves. When this arrangement is employed thesupports for'the steady bearing may be placed nearer the end where thecool oil enters than the opposite end, because as the oil passes betweenthe bearing surfaces it becomes heated and thinner, and therefore thefilms at the hotter end of the bearing should have longer moment armsthan the films at the cooler end of the bearing. In any event thesupports for the steady bearing, where the latter is made selfalining,will be in the plane of the resultant of the pressures on the filmexisting between the bearing surfaces.

Figs. 2 and 3 show, in circumferential development, two arrangements ofgrooving embodying 76 the present invention and employing air sealinggrooves 30 and 3| adjacent the opposite extremities of the bearingsurfaces. In the form shown in Fig.2 the grooving is so arranged thatthe films are not symmetrical axially of the bearing, and this issuitable for use where the steady bearing is mounted rigidly withoutprovision for selfalinement. In the form shown in Fig. 3 the grooves areshown symmetrical axially of the bearing, and this arrangement issuitable where the steady bearing is mounted with provision forself-alinement. v

In Fig. 2, assuming that the oil is delivered to the groove 30, it flowsaxially of the bearing surface through grooves 32 in the bearingsurface, then through passages 33 at the rear of the bearing surfaces,and then through grooves 34 in the bearing surface, the latter groovesdelivering to the air sealing grooves 3|. In this arrangement an elementof the bearing surface of the shaft when opposite one of the' grooves 32is substantially unsupported adjacent one end of the bearing surface,while at the opposite end of the bearing surface it is supported by theoil film between the pair of grooves 34 on either side of said grooves32. When said element is opposite one of the grooves 34 the conditionsare reversed, and the element is substantially unsupported at the latterend of the bearing surfaces while it is supported by a film extendingbetween two of the grooves 32 at the former end of the bearing surfaces.Hence there is a periodic increase and decrease of pressure adjacent theopposite extremities of the bearing surfaces, th periodicities at thetwo ends of the bearing surface being out of phase, so that the shafttends to be set into vibration.

In the form shown in Fig. 3, assuming the oil is delivered'to the groove30, it first flows axially of the shaft through grooves 35'in thebearing surface, then through passages-36 at the rear of the bearingsurfaces, then through the grooves 31 in the bearing surface disposedmidway between the'grooves 3B and 3|, then. through passages 38 at therear of the bearing. surfaces, and then through grooves 39 in thebearing surface in alinement with and of equal length to the passages35, the latter grooves 39 delivering to the groove 3!. In thisconstruction the 'oil films are balanced with respect'to the medialcircumferential line of the bearing surfaces because of the symmetricalarrangement of the oil grooves, the relation of the oil films being thesame as that described in conjunction with Fig. 1 except that the oil isflowing from one extremity of the bearing surfaces to the other insteadof being delivered midway of the length of the bearing surfaces.

The number of grooves around the bearing surface in a circumferentialdirection may be varied in conformity with the character of film actiondesired. In general it is desirable to arrange the grooves symmetricallyaround the shaft circumferentially, and the number of systems of similargrooves in a circumferentialdirection determines the tendency of theshaft to vibrate. ample, if there are four systems of similar groovesaround the circumference of the bearings there is a periodic change inthe pressure of the film opposite any given element of the bearingsurface of the shaft four times in each revolution and,

depending upon the speed of rotation of the shaft,

there is a tendency of the shaft to vibrate at the period so determined.This periodicity can be increased or decreased by increasing ordecreasing For exthe number of systems of grooves and therebysynchronization of the natural period of the shaft and the part which itcarries with the period which the film tends to set up can be avoided,and this may be taken advantage of in damping the vibratory action ofthe shaft under the action of the machinery connected thereto.

The advantages available from the use of oil grooves disposed inaccordance with this invene tion will be apparent from a considerationof some of the conditions which may exist:-

. First, the shaft may be out of balance so that it presents its loadagainst the bearing successively in every radial direction. This mayoccur regularly, as for example, with an unbalanced crankshaft, orintermittently, as for example, when a boulder gets caught in theimpeller of a dredge pump. Under these conditions the bear ing should becapable of sustaining a load directly against any portion of itscircumference. Similarly, when the bearing is to be used in a horizontalmotor for a belt drive, and the direction of belt pull is not known bythe manufacturer, the bearing should be capable of taking the belt pullin any direction. 5 .5

On the other hand, if the direction of maximum load is known, as forexample, in a motor drive where the belt pull is downward and increasesthe weight on the bearing, the axial grooves need not be equally spacedcircumferentially, but may be so arranged as to present a maximumhearing capacity in the direction of greatest load.

Vibrations existing in a shaft may be of three general types, occurringeither singly or in conjunction:

(a) when the shaft under deflection in any direction swings like ahammock.

(b) When the shaft, deflecting in a given direction, increases ordecreases that deflection like the bending of a leaf spring.

(0) In some shafts harmonics may be set up, where the nodes are at thehearings or elsewhere.

Vibration such as above described may be superimposed upon a shaft thatis rotating with 15 an unbalanced load so that the shaft swings in itsbearings like a skipping rope. In that case it presents its pressureagainst the bearing surfaces in every radial direction successivelyduring each turn of the rope, which may or may not coincide with therevolution of the shaft itself.

Generally speaking, balanced grooving is desirable in order to preventmetallic contact which might occur if the film was allowed to become toothin at either end of the bearings, due to shaft deflection, bearingrigidity, or misalinement from other causes.

It will be understood that the passages 33, 3S and 38 of Figs. 2 and 3are separated from the bearing surface in order to prevent the fallingof the oil'pressure to or near atmospheric pressure in the regionsbetween the inner ends of the axial grooves, and reducing the effectivebearingarea. Obviously, these passages may be formed in the bearingsurface if deemed desirable, and if arcuate in extent they will act aspumps to assist or oppose the flow of oil.

Fig. 4 shows more or less schematically a combined thrust and steadybearing, embodying the present invention, for use in conjunction withhorizontal or inclined shafts, and in some respects is similar to theembodiment of Fig. 1. In this embodiment the shaft 5 is provided with athrust collar 45 with which cooperates stationary thrust bearingelements shown more or less diagramrounding the thrust bearing elementsand theshaft is a casing which is secured in any suitable way, as bymachine screws 41, to the base 'or foundation 48. Casing 46 not onlyafi'ords a housing for the thrust bearing element at its portion 49 oflarger diameter, but also constitutes a casing 50 for the journalhearing at its portion of smaller diameter, where it is shown asprovided with a babbitt lining 5| containing oil grooves 52 of thecharacter disclosed in the preceding. figure s. Said grooves 52communicate with an air sealing oil groove 53 adjacent the outerextremity of the journal bearing surfaces, and the oil is returned fromsaid groove 53 to the body of oil in the oil pot 54, also carried by thebase or foundation 48, through one or more suitable grooves 55 in saidbase or foundation. An oil collecting groove 56 is also shown ascommunicating with the passage 55. Oil is supplied to the journalbearing surfaces from the space containing the thrust bearing elementsthrough one or more suitable passages 51 in the casing 46, whichpassages communicate with the oil grooves 52 at one extremity and withthe chamber containing the thrust bearing elements at the otherextremity. The oil may be supplied to the chamber containing the thrustbearing elements in any suitable way, as by a viscosity pump 68,coacting with the periphery of the thrust collar 45. If desired, theviscosity pump may be so constructed as to collect and feed oil to thebearing surfaces for either direction of rotation of shaft 5.

It will therefore be perceived that a combined thrust and steady bearinghas been provided wherein the support for the steady bearing is entirelyindependent of the size and shape of the pot or bearing housing, but maybe determined bythe size of the thrust bearing, so that the support forthe steady bearing may be standardized and the steady bearing may befurnished as a unit. Moreover, the steady bearing may be P madeself-alining and lubricated by oil supplied from the thrust bearing ifdesired; Provision has also been made to prevent the drawing of air intothe oil film, and to maintain the desired balance of the oil films, andto prevent or control or predetermine or damp the vibratory action ofthe shaft, and these features may be embodied in various forms ofjournal bearings as well as in,

steady bearings. Additionally, these features may be combined in variousways to securethe desired results. 1;

While a number of embodiments of the invention have been shownanddescribedin detail, it is to be expressly;understood that" theillustrated embodiments are not exclusive, as various other embodimentswill now readily suggest themselves to those skilled in the art, whilechanges may be made in the details of constructinn, arrangementand'proportion of parts, and certain features used without otherfeatures, without departing from the spirit of the invention. Referenceis therefore to be had to the claims hereto appended for a definition ofthe limits of the invention.

What is claimed is:

1. In a journal bearing, relatively rotatable bearing memmrs providedwith circumferential air seal oil grooves to be filled with oil andthereby exclude air from the oil film, said grooves being disposedadjacent each extremity of the bearing surfaces, axially extending oilgrooves intermethe air seal oil groove for collecting oil leaking fromsaidair seal oil groove along the shaft.

2. In a' journal bearing, relatively rotatable bearing members providedwith circumferential air seal oil grooves to be filled with oil andthereby exclude air from the oil film, said grooves being disposedadjacent each extremity of the bearing surfaces, axially extending oilgrooves intermediate said air seal grooves for forming a pluralityofcircumferentially arranged oil films between the bearing surfaces, saidoil grooves communicating with said air seal'grooves for free fiow ofoil therebetween, means for circulating oil to and through said oilgrooves to fill said air seal grooves with oil above external airpressure whereby the oil in said grooves supplies oil to said films uponthe occurrence of a negative pressure therein, means to return the oilflowing through said air seal oil grooves at a rate adapted to maintainsaid grooves full of oil and an oil collecting channel axially beyondand separate from the air seal oil groove for collecting and returningoil escaping from said air seal oil groove along the shaft.

3. In a journal bearing, relatively rotatable bearing members providedwith a circumferential air seal ofl groove to be filled with oil andthereby exclude air from the oil film, said groove being disposedadjacent anextremity of the bearing surfaces and filled with oil aboveexternal air pressure whereby the oil in said groove supplies oil to thefilm between said bearing surfaces upon the occurrence of a negativepressure in said film, means for circulating a copious supply of ofl toand through said groove to fill the same, means to return the oilflowing through and out of said groove at a rate adapted to maintainsaid groove full of oil and an oil passage axially beyond said air sealoil groove for collecting oil escaping ax- 60 ially therefrom.

4. In a journal bearing, relatively rotatable bearing members providedwith a circumferential air seal oil groove to be filled with oil and.thereby exclude air from the oil fihn, said groove being disposedadjacent an extremity of the bearing surfaces, means communicating withsaid groove and adapted to maintain an oil film having a lateral edgedefined by said groove, said means also adapted to maintain said groovefull 60 of 011 above external air pressure whereby it may supply 011 tosaid film and exclude air therefrom, means to return the oil flowingthrough said groove, and an oil collecting channel axially beyond saidair seal oil groove for collecting oil 65 escaping axially therefrom.

5. In a journal bearing, relatively rotatable bearing members providedwith a plurality of axially extending oil grooves for distributing oilto the bearing surfaces, forming a plurality of circumferentiallyarranged oil films, a circumferential oil groove adjacent an extremityof the bearing surfaces and communicating with said oil grooves for freefiow of oil therebetween, and means for circulating oil to and throughsaid first named oil grooves to form oil films and fill saidcircumferential groove, said last named groove being maintained full ofoil whereby an oil seal is formed to prevent the entry of air into theoil film, and an oil collecting groove axially outside of and separatedfrom said air seal oil groove.

6. In a self-alining journal bearing, in combination with meansproviding an axis about which alining movement is effected, relativelyrotatable bearing members provided with circumferentially arranged setsof grooves spaced axially by a circumferential zone of bearing surfaceand arranged symmetrically with respect to the radial plane of saidaxis, and means for feeding oil to said grooves and communicatingtherewith substantially in the radial plane of said axis.

'7. In a self-alining journal bearing, in combination with meansproviding an axis about which alining movement is effected, relativelyrotatable bearing members provided with circumferentially arranged setsof axially extending staggered oil grooves spaced axially by acircumferential zone of bearing surface and symmetrically arranged withrespect to the radial plane of said axis, and means for feeding oil tosaid grooves substantially in the plane of said axis.

8. In a self-alining journal bearing, in combination with meansproviding an axis about which alining movement is effected, relativelyrotatable bearing members provided with circumferentially arranged setsof oil grooves extending for only a portion of the axial length of thebearing surfaces and axially spaced by a circumferential zone of thebearing surface, said grooves being symmetrically arranged with respectto the radial plane of said axis to produce oil films which are balancedwith respect to said axis.

9. In a self-alining journal bearing, in combination with meansproviding an axis about which alining movement is effected, relativelyrotatable bearing members provided with circumierentially arrangedaxially spaced sets of oil grooves extending for only a portion of theaxial length of the bearing surfaces and communicating for flow of oilfrom one to another through connecting channels disposed rearwardly ofsaid bearing surfaces, said oil grooves being symmetrically arrangedwith respect to the radial plane of said axis.

10. In a self-alining journal bearing, in combination with meansproviding an axis about which alining movement is effected, relativelyrotatable bearing members provided with circumferentially arranged setsof staggered oil grooves separated by a circumferential zone of thebearing surface and communicating through connecting channels disposedrearwardly of said zone for flow of oil from one to another of saidgrooves, said grooves being symmetrically arranged with respect to theradial plane of the axis.

11. In a journal bearing, relatively rotatable bearing members providedwith circumferentiallyarranged axially-spaced sets of oil groovessymmetrically arranged with respect to the circumferential medial lineof the bearing, and one or more circumferential air seal oil groovesadjacent the extremity of the bearing surfaces and communicating withsaid first named grooves for free flow of oil therebetween.

12. In a journal bearing members provided with circumferentiallyarrangedsets of oil grooves spaced axially by a circumferential zone of thebearing surface and arranged symmetrically with respect to thecirbearing, relatively rotatable cumferential medial line of thebearing, and means for feeding oil thereto at said circumferentialmedial line.

13. In a journal bearing, relatively rotatable bearing members providedwith circumferentially- 5 arranged axially-spaced sets of oil grooveswhich are symmetrically arranged with respect to the circumferentialmedial line-of the bearing, air sealing oil grooves at each extremity ofthe bearing surfaces communicating with said first named grooves forfree fiow of oil therebetween, and means for feeding oil to one of saidlast named grooves.

14. In a journal bearing, relatively rotatable bearing members providedwith axially extending oil grooves adjacent each extremity of thebearing surfaces and in the medial zone of the bearing surfaces, andpassages at the rear of the bearing surfaces communicating at theiropposite ends with said oil grooves for flow of oil from one to anotherof said grooves.

15. In a journal bearing, relatively rotatable bearing members providedwith axially extending oil grooves adjacent each extremity of thebearing surfaces and with axially extending oil grooves in the medialzone of said bearing surfaces, said last named oil grooves beingstaggered with respect to said first named oil grooves, and passages atthe rear of the bearing surfaces communicating at their opposite endswith said grooves for flow of oil from one to another of said grooves.

16. In a journal bearing, relatively rotatable bearing-members providedwith axially extending oil grooves adjacent each extremity of thebearing surfaces and in the medial zone of the bearing surfaces,passages at the rear of the bearing surfaces communicating at theiropposite ends with said oil grooves for flow of oil from one to anotherof said grooves, and one or more air sealing circumferential oil groovesadjacent the extremity of the bearing surfaces.

17. In a journal bearing, relatively rotatable bearing members providedwith axially extending oil grooves adjacent each extremity of thebearing surfaces and in the medial zone of the i5 bearing surfaces, saidgrooves being symmetrically arranged with respect to the medialcircumferential line of the bearing, and passages at the rear of thebearing surfaces communicating at their opposite ends with said oilgrooves for flow of oil from one to another of said grooves.

18. In a steady bearing, relatively rotatable steady bearing members andmeans for mounting the stationary bearing member whereby it is self-alining, said stationary bearing member being provided with a pluralityof circumferentiallyarranged sets of oil grooves which are separated bya circumferential zone of bearing surface and arranged symmetricallywith respect to said mounting means.

19. In a steady bearing, relatively rotatable steady bearing members andmeans for mounting the stationary bearing member whereby it isself-alining, said stationary bearing member being provided with aplurality of circumferentiallyarranged sets of oil grooves symmetricallyar ranged with respect to said mounting means and with one or morecircumferential air sealing oil grooves communicating therewith for freeflow of oii therebetween and disposed adjacent the extremity of thebearing surfaces.

20. In a steady bearing. relatively rotatable steady bearing members andmeans for mounting the stationary bearing member whereby it is selfalining, said stationary bearing member being ing the stationary bearingmember whereby it is self-alining, said stationary bearing member beingprovided with axially extending oil grooves shorter than the axiallength of the bearing surfaces and in communication for flow of oil fromone to another through passages at the rear of the bearing surfaces, andsaid grooves being symmetrically arranged with respect to the medialcircumferential line of the bearing.

22. In a steady bearing, relatively rotatable steady bearing members andmeans for mounting the stationary bearing member whereby it isself-alining, said stationary bearing member being provided with axiallyextending oil grooves shorter than the axial length of the bearingsurfaces and in communication for flow of oil from one to anotherthrough passages at the rear of the bearing surfaces and said oilgrooves being symmetrically arranged with respect to the medialcircumferential line of the bearing and communicating with one or .morecircumferential oil grooves adjacent the extremity of the bearingsurfaces.

23. In a steady bearing, relatively rotatable steady bearing members andmeans for mounting the stationary bearing member whereby it isself-alining, said stationary bearing member being provided. withsymmetrically arranged, staggered, axially extending oil groovescommunicating for flow of oil from one to another through passages atthe rear of the bearing surfaces and one or more circumferential oilgrooves communicating therewith anddisposed adjacent the extremity ofthe bearing surfaces.

24. In a journal bearing, relatively rotatable bearing members providedwith axially extending oil grooves adjacent each extremity of thebearing surfaces, and intermediate passages at the rear oftthe bearingsurfaces communicating at their opposite ends with said oil grooves forflow of oil from one to another of said grooves.

25. In a Journal bearing, relatively rotatable bearing members providedwith axially extending oil grooves adjacent each extremity of thebearing surfaces, said oil grooves being staggered with respect to eachother, and intermediate passages at the rear of the bearing surfacescommunicating at their opposite ends with said oil 14 grooves for flowof oil from one to another of said grooves.

26. In a journal bearing, relatively rotatable bearing members providedwith axially extending oil grooves adjacent each extremity of the 15bearing surfaces, intermediate passages at the rear of the bearingsurfaces communicating at their opposite ends with said oil grooves forflow of oil from one to another of said grooves, and one or more airsealing oil grooves adjacent the 20 extremity of the bearing surfaces.

27. In a journal bearing, relatively rotatable bearing members providedwith axially extending oil grooves adjacent each extremity of thebearing surfaces, and intermediate passages at the 25 rear of thebearing surfaces communicating at their opposite ends with said oilgrooves for flow of oil from one to another of said grooves, said oilgrooves being symmetrically arranged around the circumference of thebearing surfaces. 30

28. In a steadybearing, relatively rotatable steady bearing members andmeans for mounting the stationary bearing member whereby it isself-alining, said stationary bearing member being provided with acircumferential zone of 0 bearing surface in radial alinexnent with saidmounting means and with a plurality of sets of circumferentiallyarranged axially extending oil grooves for forming a plurality of setsof circumferentially arranged oil films which are axially spaced by saidcircumferential zone of bearing surface and balanced with respect tosaid mounting means.

HARRY A. S. HOWARTH. 5

